Hybrid coated cosmetic powders and methods of making and using same

ABSTRACT

A hybrid coating material and process for pigments and other powders, for example cosmetic powders employs an organometallate, for example a titanate, and a functionalized silicon compound, for example a trialkoxysilane or a functionalized polysiloxane, which covalently bond to each other and to the substrate powder. The coated powders can exhibit excellent hydrophobicity coupled with lipophilicity. Employment of fluorinated silicon compounds may provide hydrophobicity and lipophobicity. Examples show good dispersibility of coated pigments in aqueous, oil and silicone fluids.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of Schlossman et al.provisional patent applications No. 60/451,056, filed Feb. 28, 2003(attorney docket number DS4) and 60/472,527 filed May 22, 2003 (attorneydocket number DS410), the disclosures of each of which provisionalpatent applications are hereby incorporated herein by reference thereto.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] (Not applicable.)

BACKGROUND OF THE INVENTION

[0003] The present invention relates to novel hybrid coated cosmeticspowders and methods of making and using same. More particularly, theinvention relates to novel compositions and methods for coatinginsoluble cosmetics powders, for example inorganic and organic, pigmentsand fillers, to the coated powders produced, to cosmetic and otherformulations incorporating such coated powders and to methods of makingand using said coated powders and formulations. Preferred embodiments ofthe invention include novel coated cosmetic powders having a uniquecombination of excellent hydrophobic and lipophilic properties which isparticularly advantageous in many cosmetic applications.

[0004] Most cosmetics formulations include in their compositionscosmetic powders, finely divided particles of solid, insolublematerials, for example pigments and fillers, that can serve a variety offunctions, such as providing desired visual properties such as opacityand color, desired tactile properties such as viscosity and feel,special effects such as pearlescence and iridescence and various otherdesirable properties, for example oil absorbency. Cosmetic powdersinclude inorganic materials such as metal oxides, silicates andcarbonates as well as organic pigments or lakes such as ultramarine andcrimson lake and polymeric particulates such as nylon and cellulose.Additional examples of pigments that can be employed in the presentinvention are set forth hereinbelow. Some examples of cosmeticformulations employing powders include liquid or powder makeups andfoundations, moisturizing and antiaging creams and lotions, nail polish,lipstick, mascara and eye shadow, to name but a few.

[0005] Primarily because of their surface characteristics, it may bedifficult to satisfactorily incorporate raw, untreated powders intoliquid or powdered cosmetic bases or excipients in a manner providinguniform stable dispersions. Desirably, the powders should be uniformlydistributed throughout the base or excipient medium and the dispersionshould remain stable over time with no significant settling oragglomeration occurring before the product is eventually used by the endconsumer, which can be as much as two or more years after manufacture.It is also desirable that the powders should not impart unaestheticcharacteristics to the end-product cosmetic formulation, such as agritty or sandy feel, which may result from agglomeration of powderparticles or the presence of oversized particles in the pigment powder,discoloration attributable to non-uniform distribution of the powder,and other negative characteristics such as settling.

[0006] Many pigment materials for example metal oxides and carbonates,have a somewhat hydrophilic surface, or bear hydrophilic moieties orions on their external surfaces which render the powder particles proneto agglomerate in aqueous media which are commonly employed incosmetics.

[0007] Accordingly, over the years, many compositions and methods havebeen employed and proposed for treating or coating insoluble cosmeticpowders, in order to overcome these and other problems. Such priorproposals have met with considerable success and it is now standardpractice in the cosmetics industry to coat powders for cosmetic use. Inparticular, it is well known to “hydrophobize” cosmetic powders, whichis to say to treat the powders to render them more hydrophobic, thusproviding more stable dispersions (or suspensions) in aqueous media.

[0008] Powders can be hydrophobized by treatment with a suitable coatingagent in a liquid medium, for example by mixing or spraying the coatingagent with or on to the powder and heating the mixture, optionally undervacuum to remove volatile solvents, if employed. Preferred coatingagents are chemically reactive with the substrate powder to provide adurable covalent bond thereto and have hydrophobic chemical backbones orsubstituents that can provide a hydrophobic outer layer, skin or shellaround each individual powder particle. The coating agent may react, forexample, with hydroxyl groups, oxide ions, available oxygen atoms orother suitable reactive groups normally present on the surface of thecosmetic powder being coated.

[0009] Mitchell Schlossman U.S. Pat. No. 4,877,604 (“Schlossman '604”hereinafter), the disclosure of which is herein incorporated byreference thereto, discloses and claims the use of organotitanates, tocoat pigments and other cosmetic powders, one preferred coating agentbeing isopropyl titanium triisostearate. Schlossman '604 discloses thatthe claimed coating materials and methods can provide uniform and stabledispersions of pigments and other cosmetic materials, such as talc,sericites and mica. Such dispersion uniformity can avoid the need tocolloid mill the final emulsion to achieve smoothness and homogeneity invarious cosmetic products, for example, in oil-in-water liquid makeups,avoiding settling or segregating out of pigments or other cosmeticmaterial thereby increasing the shelf-life of the product. In addition,the use of Schlossman '604's titanate-treated pigments in liquid pigmentand/or color extenders can improve the viscosity range providing moreuniform extenders and enabling extenders to be utilized withoutadversely affecting the viscosity of the final product.

[0010] Other advantages to using treated or coated materials inaccordance with Schlossman '604 include increased water resistance dueto hydrophobic characteristics, reduced need for powder blends,increased smoothness on application of anhydrous and powder blends,better skin adhesion, better appearance of frosted products, lessstreaking in pressed and anhydrous makeup products and noticeablesmoothness and ease of manufacture of compact cream makeup.

[0011] Thus, the Schlossman '604 organometallate coating materialsprovide an array of attractive features. Pursuant to the insights of theinvention, it would be desirable to provide coatings for cosmeticpowders which retain these benefits and which can extend potential usesof the resultant coated powders to environments where isopropyl titaniumtriisostearate treated pigment may not always be satisfactory, forexample in silicone fluids and in low pH media. The latter are oftenrequired for skin care products containing alpha-hydroxy acids.

[0012] It is also known to employ functionalized silanes, including forexample, triethoxy octylsilane to provide a silicone coating on cosmeticpowders to render them hydrophobic. With regard to terminology, it isnotable that even extensively substituted derivatives of silane, such astriethoxy decyl silane are sometimes generally referenced in the art bythe catch-all phrase “silanes”. While silane-coated powders may displaygood hydrophobicity they may not be adequately lipophilic for somepurposes yielding unacceptably viscous dispersions in cosmetic oils suchas mineral oil. A further problem is that silicone coated pigments maydisplay color shift over time. Hollenberg et al. U.S. Pat. No. 5,143,722is but one example of a disclosure of silane coated cosmetic pigmentsproviding silicone coated pigment powders.

[0013] The foregoing description of background art may include insights,discoveries, understandings or disclosures, or associations together ofdisclosures, that were not known to the relevant art prior to thepresent invention but which were provided by the invention. Some suchcontributions of the invention may have been specifically pointed outherein, whereas other such contributions of the invention will beapparent from their context. Merely because a document may have beencited here, no admission is made that the field of the document, whichmay be quite different from that of the invention, is analogous to thefield or fields of the invention.

BRIEF SUMMARY OF THE INVENTION

[0014] The present invention solves the above mentioned problems of therelated arts by providing a process of coating any one or more of a widerange of cosmetic or other powders with a novel hybrid coating agentcomprising reacting a combination of a an organotitanate or othersuitable hydrophobizing organometallate and a functionalized siliconcompound with the powder or powders to produce hybrid coated powders.The invention enables a wide range of powders to be effectively coatedto have a number of desirable properties such as good water repellency,good stability, a smooth feel and good adhesion to the skin to beproduced. The powders that may be coated include common cosmetic powderssuch as metal oxide pigments and metal carbonate, silicate or otherfillers, as well as more exotic powders such as sericites and metaloxide coated micas. Preferred hybrid coated powders of the inventiondisplay all of these properties. The invention also provides novelprocesses for producing the coated cosmetic powder and cosmetics madewith the treated pigment or other powder.

[0015] Preferably, both the organometallate and the functionalizedsilicon compound are sufficiently reactive to covalently bond with thepowder and each have chemical structures providing hydrophobicity to thecoated powder. In addition it is particularly preferred thatorganometallate and the functionalized silicon compound are capable ofreacting with each other. Preferably also, the organometallate andsilicon compound are selected so as to avoid impeding each other'sfunctionality.

[0016] The functionalized silicon compound can be any one, or a mixture,of a wide range of compounds including a functionalized silane, afunctionalized silicone, e.g. a polysiloxane, or fluorinated analogs ofthe foregoing.

[0017] In one embodiment, the invention provides a cosmetic powder, forexample a pigment, extender pigment or filler, treated or coated with ahybrid coating agent comprising an organic titanate and atrialkoxyalkylsilane. After reaction in the processes of the invention,for example by heat treatment, these compounds become chemically bondedto the surface of the pigments or fillers.

[0018] Coated pigment powders according to the invention may have bothhydrophobic and lipophilic properties or both hydrophobic and lipophobicproperties. Use of fluorinated silicon compounds can provide thelipophobic properties.

[0019] Some embodiments of coated pigment powder according to theinvention have hydrophobic and lipophilic properties and are alsodispersible in silicone fluids.

[0020] The treated pigments have good adhesion to the skin, and abilityto permit color pigment of fine particle size to spread well, and isparticularly suitable for use in cosmetics such as powder, oil-in-waterand water-in-oil emulsions and anhydrous makeup like lipstick.

DETAILED DESCRIPTION OF THE INVENTION

[0021] The present invention provides a process for hydrophobizing avariety of cosmetic powders, including pigments, lakes of organiccolorant and filler, and formulations in which the such treated powderscan be applied. The invention extends to the coated powders produced, tothe novel methods of formulating cosmetic products and to the novelcosmetic products that result. In particular, the invention providesnovel coated powders, especially but not exclusively cosmetic powders,which, in preferred embodiments of the invention, are highly hydrophobicand uniquely dispersible in both hydrocarbon-based oils, or lipids, andin silicone fluids.

[0022] These desirable properties can be obtained by coating any one ormore of a wide range of cosmetic powders with a novel combination ofcoating agents pursuant to the invention, namely an organometallate anda reactive silicon compound, to provide a durable hybrid coating on thepowder particles.

[0023] It is desirable that both coating agents are sufficientlyreactive to covalently bond with the target particles, under theconditions of the coating process, to provide a reaction product whichis stable to subsequent processing and storage conditions.

[0024] It is preferred that each coating agent residue becomeschemically covalently bound to the surfaces of the powder particles andcontributes to the provision of a durable outer layer or skin of ahybrid chemical nature, including metal atoms, silicon atoms andpossibly M—O—Si groups, as described herein, which layer or skinenvelops each powder particle.

[0025] Preferably at least one of the coating agents comprises abifunctional coupling agent capable of covalently bonding not only withthe target substrate powder but also with the other coating agent, orone of the other coating agents if more than two are employed. To thisend, the bifunctional coupling agent may have two or more functionalentities, which may be the same or different and which between themprovide the desired reactivity with the substrate powder and the othercoating agent or materials. More preferably, both coating agents arebifunctional, providing the possibility of oligomeric or polymericchains comprising residues of both starting materials being present inthe coating.

[0026] The beneficial high dispersibility in two different classes ofliquid media, coupled with excellent hydrophobicity and waterrepellency, is especially attractive to formulators in the cosmeticsindustry enabling the inventive hybrid coated powders to be specifiedfor a wide range of applications without undue concern as to the natureof the liquid phase into which the powder is to be dispersed.Furthermore, the inventive hybrid coatings are suitable for a wide rangeof cosmetic powders including many or most of the powders used ineveryday cosmetic products such as liquid or powder makeups, lipsticks,nail enamels, eye shadows, mascaras and so on. Thus the formulator mayfreely specify cosmetic powders having the inventive hybrid coatings tomeet an exceptionally diversified range of cosmetics requirements. Theinvention further more enables the formulator to specify one type ofcoating, the hybrid coating of the invention to be employed for all thepowder ingredients of a cosmetic formulation without concern as to theliquid media to be employed in the formulation or as to possibleincompatibilities between different coatings.

[0027] Possibly, one of the coating agents, for example theorganometallate, may comprise a bifunctional coupling agent, asdescribed above, while the other coating agent, in this exemplary casethe silicon-containing compound, is reactive with the one coating agentbut not the target powder, for example by way of a hydroxyl substituent.Such a combination can provide a bilayer shell-like coating on theparticles comprising for example an outer shell of silicon-containingmoieties, being the residues of the silicon-containing compound coupledto the substrate powder through an inner shell of organometallateresidues.

[0028] In one preferred embodiment, the invention relates to cosmeticpowders treated with a mixture of organotitanate and trialkoxyalkylsilane coating agents to provide a coating that is hydrophobic andlipophilic or lipophobic. The invention also provides processes for theproduction of such coated powders and cosmetic formulations comprisingthe cosmetic powders treated with the novel combination of coatingcompounds or agents.

[0029] Organometallates

[0030] Any organometallate compatible with the purposes of the inventionmay be employed in the novel compositions, materials and processesdescribed herein. Many suitable organometallates, and equivalentcompounds, additional to those described or suggested herein will beapparent to those skilled in the art in light of the disclosure hereinor will become apparent as the art develops. Non-limiting examples ofequivalent compounds or compositions are compounds or compositions whichfunction as precursors yielding one or more suitable organometallates insitu.

[0031] Organometallate compounds to be employed in the invention arepreferably chosen to provide hydrophobic residual units in the powdercoating. They may, for example, comprise metallate compounds wherein atleast one enduring, unreactive, hydrophobic organic group, such as asaturated hydrocarbon, possibly containing one or more phenyl groups, iseach attached to a metal atom by an oxygen atom and at least onedisplaceable groups or atoms is also attached to the metal atom by anoxygen atom to provide a functional group. The enduring group endures tobecome a hydrophobic residue in the powder coating while the functionalgroup is removed in the coating process, preferably yielding an M—Ogroup in the coating compound. The residue in the coating should becosmetically compatible. For this reason, organometallates of toxicmetals such as lead, cadmium and mercury are to be avoided.

[0032] To this end the organometallate compounds may comprise one ormore relatively unreactive hydrophobic organic groups, e.g. estergroups, covalently bonded to a metal atom, and one or more relativelyreactive groups, or functional entities e.g ether or alkoxy groups, alsocovalently bound to the same metal atom. The ester or other

[0033] The organometallate compound can have from one to five functionalentities depending upon the valence state of the metal. However from oneto three functional entities is preferred with organometallic compoundshaving two functional entities for example two alkoxy groups, especiallytwo methoxy or two ethoxy groups, being particularly preferred for usein the practice of the invention. Organometallates with two or morefunctional entities may be described as “coupling agents”.

[0034] Some suitable organometallate compounds for use in the presentinvention have a structure illustrated by the following Formula 1

(R¹O—)_(x)M(—OOCR²)_(y)  (1)

[0035] wherein:

[0036] R¹ is a saturated, unsaturated or polyunsaturated, straightchain, branched or unsubstituted or substituted cyclic alkyl grouphaving from 1 to 12 carbon atoms, preferably from 1 to 4 carbon atoms;

[0037] R² is a saturated, unsaturated or polyunsaturated, straightchain, branched, unsubstituted cyclic, substituted cyclic alkyl or alkylphenyl group having from 3 to 60 carbon atoms, preferably from 7 to 25carbon atoms;

[0038] M is a cosmetically compatible metal capable of forming thecompound shown with a valence state of z; and x+y=z.

[0039] In some useful or preferred embodiments of the invention:

[0040] R¹ is a saturated straight chain or branched alkyl group havingfrom 1 to 4 carbon atoms, for example, methyl, ethyl or isopropyl;

[0041] R² is a saturated straight chain or branched alkyl group havingfrom 7 to 25 carbon atoms, for example octyl, decyl, stearoyl, or cumyl;and

[0042] M is a metal with a valence state, z, of 2, for example zinc, ametal with a valence state, z, of 3, for example aluminum, a metal witha valence state, z, of 4, for example, tin, titanium or zirconium, or ametal with a valence state, z, of 5, for example vanadium. Metals with avalence state of 3 or higher are preferred.

[0043] In the following description, where reference is made to titaniumor to organotitanate compounds it will be understood that other metalsor organometallates such as tin, vanadium, zinc and zirconium and theirorganometallates that are suitable for the purposes of the invention maybe used mutatis mutandis in place of titanium or organotitanates, unlessthe context suggests indicates otherwise.

[0044] The organotitanate structures illustrated by Formula 1 and whichcan be employed in the practice of the invention include, for the casewhere M is titanium, not only monoalkoxy titanates, but also di- andtri-alkoxy titanates. Monofunctional organometallates, such asmonoalkoxy titanates, can couple to the pigment surface and also tosuitably functionalized silicones. However, multifunctionalorganometallates, for example di- and tri-alkoxy titanates, areparticularly advantageous for use in the invention for and can provide anumber of benefits such as: greater reactivity of the organometallate,for example enhanced ability to bind to the substrate powder; ability tocatalyze reaction of functionalized silicon compounds with substrate thesubstrate powder and with the titanate; and the ability to crosslinkwith reactive silicon compounds.

[0045] Some limited polymerization of multifunctional organometallatesmay occur with bonding of the resultant oligomers or polymers to thepowder substrate. However, it is believed that such organometallateoligomers or polymers in many cases may not be sufficiently stable toyield residues in the end-product coated powders or may not survivepost-processing, for example formulation into creams or lotions.

[0046] Some suitable hydrophobizing organometallate compounds for use inthe practice of the present invention include organotitanate compoundsof the following Formula 2:

[0047] wherein:

[0048] m is from 1 to 4; and

[0049] n is from 7 to 25, preferably from 12 to 20.

[0050] The length of each fatty acid chain may be the same or different.

[0051] It will be understood that other suitable organometallatecompounds can be employed wherein in Formula (2) titanium is replaced bya suitable metal such as aluminum, tin, vanadium, zinc or zirconium withthe formula being adjusted for the metal valence state, as may benecessary, for example by adjusting the number of ester groups, thealkoxy group being retained. Thus, suitable organoaluminates,organostannates, organovanadates, organozincates or organozirconates maybe employed

[0052] Some specific organometallates suitable for use in the inventioninclude: liquid monoalkoxy (C₁ to C₂₀) isostearoyl titanates, especiallyisopropyl triisostearoyl titanate; isopropyl dimethacryl isostearoyltitanate and isopropyl dimethacryl isostearoyl titanate and coordinatetitanates such as tetraisopropyl (di(dioctyl) phosphito titanate andtetra (2,2 diallyoxymethyl) butyl, di(ditridecyl) phosphito titanate;organotitanates disclosed in “The Chemistry of Titanate CouplingAgents”, pages 2-9 and 26-29 in “Ken-React Reference Manual—Titanate,Zirconate and Aluminate Coupling Agents”, Monte et al., M. SchlossmanU.S. Pat. No. 4,877,604; and the titanate coupling agents disclosed inMonte et al. U.S. Pat. No. 4,098,758, the disclosure of each of whichreferences is hereby incorporated herein by reference thereto.

[0053] Other organometallates that may be used include:

[0054] isopropyl tri(dioctyl) pyrophosphato titanate, di(dioctyl)pyrophosphato oxoethylene titanate, di(dioctyl) phosphato ethylenetitanate, di(dioctyl) pyrophosphato ethylene titanate, tetraoctyltitanate di(ditridecyl) phosphite, and dialkoxy bis(triethanolamine)titanate;

[0055] aluminates such as diisopropyl acetoalkoxy aluminate, isopropyldiisostearoyl aluminate, and isopropyl dioctyl phosphato aluminate;

[0056] zirconates such as isopropyl triisostearoyl zirconate, butyltriisostearoyl zirconate, butyl trioleoyl zirconate, isopropyltrilinoleoyl zirconate, di(cumyl)phenyl oxoethylene zirconate,di(cumyl)phenyl dibutyl zirconate and tri(cumyl)phenyl propyl zirconate;and

[0057] vanadate and zincate analogs or equivalents of the foregoing.

[0058] Other coupling agents can also be used with similar effect andadvantage, for example, zirconate or aluminate coupling agents such asneopentyl (diallyl) oxyl, tri(dioctyl) phosphito zirconate andequivalent aluminates. However, titanates constitute a preferredspecies. Furthermore, analogous titanate coupling agents havingdifferent proportions of hydrolyzable to non-hydrolyzable groups fromthose disclosed by Monte, can be used. There is a great diversity ofsubstituents that can be present on the coupling agent. Some examples ofthese are set forth in Monte (supra). Others will be apparent to thoseskilled in the art in light of the disclosures herein. Still others maybecome apparent as the art develops.

[0059] Still further organometallates providing cosmetically compatibleresidues that can be employed in the present invention will be known tothe art. Some of these further organometallates are disclosed in:Guillissen U.S. Pat. No. 2,732,320, for example at column 4, lines25-42; Kohn et al. U.S. Pat. No. 3,014,826, for example at column 2,lines 17-23; Rauner U.S. Pat. No. 3,015,637, for example at column 2,line 39 to column 3, line 3; Hartlein U.S. Pat. No. 3,647,846 (DowCorning) for example at column 2, lines 34 to 63; Ona et al. U.S. Pat.No. 4,399,247, for example at column 4, line 35 to column 5, line 18;the disclosures of which patents are hereby incorporated herein byreference thereto.

[0060] If desired, the organometallate may be chelated, for example by amono-or polydentate chelating ligand or group which can be bonded to theorganometallate such, for example, as one or more ethylenicallyunsaturated groups (e.g. acrylic, methacrylic or vinylic), halogenatedgroups, hydroxylated groups, carboxylated groups, thiol groups, epoxygroups, ester groups, amine groups, urea groups, urethane groups,acetoacetate groups or a group derived from EDTA and its derivatives.Some examples of possible chelating groups or ligands include carboxylicacids, □-ketones, □-diketones, □-keto esters, □-keto amines, (□- and□-hydroxy acids, amino acids, preferably □-hydroxylated amino acids,salicylic acid and derivatives thereof, some specific examples of whichare acetoacetoxyethyl methacrylate, methyl □-hydroxymethacrylate,—N-methacryloyl-L-lysine, 4- or 5-methacrylaminosalicylic acid.

[0061] While the invention is limited not by any particular theory, butonly by the accompanying claims, it is contemplated that theorganometallate compound will catalyze, promote or participate in thebinding of the functionalized silicone compound with the substratepowder particles. Such favorable activity is helpful in assuring morecomplete reaction of the functionalized silicone compound, leading tostable coatings with low proportions of unreacted functional entities.Such higher stability is believed to be of particular value for thecoating of pigments in preventing or eliminating color shift over time,a problem which may occur with conventionally coated pigments. Suchcontrol of color shift is of particular value in the cosmetics and otherindustries where high quality and consistent appearances are demanded byend product consumers.

[0062] Functionalized Silicone Compounds

[0063] Any suitably functionalized silane, functionalized polysiloxane,functionalized fluorinated or fluoroalkyl silane or polysiloxane, orother appropriate functionalized silicon compound compatible with thepurposes of the invention, may be employed as a coating agent in thenovel compositions, materials and processes described herein.Preferably, the functionalized silicone compound employed is providedwith at least one functional entity capable of covalently bonding to atarget pigment surface, either directly or through an organometallateresidue, under the reaction conditions employed in the coating processesof the invention.

[0064] A preferred functional entity is a lower alkoxy group covalentlybonded directly to a silicon atom and having from one to four carbonatoms. Other functional entities such as halo atoms, preferably chloro,amino groups, imino groups, and/or hydroxyl groups may be employed, asis known to those skilled in the art. Still other functional entities orgroups that may be employed if desired, so long as they provide adequatecoupling functionality for the purposes of the invention includeethylenically unsaturated groups such as acrylic, methacrylic, vinylicgroups or the like, halogenated groups, hydroxylated groups, carboxyl orcarboxylated groups, thiol or mercaptan groups, epoxy groups, estergroups, urethane groups, urea groups, amino acid groups, polypeptidegroups and so on.

[0065] Furthermore, groups that are largely unreactive in conventionalcoating processes, for example Si—H groups in polysiloxane compounds,e.g. methicone, may have sufficient reactivity in the presence of theorganometallate compounds employed in the present invention to be usefulas functional entities. Thus, for example, methicone, having a backboneof methyl hydrogen siloxy groups can be employed as a functionalizedsilicone compound in the practice of the invention without addition ofother functional entities. Equivalent compounds having fewer reactivebackbone hydrogen atoms may also be employed.

[0066] It can also be advantageous for the silicone compound to havemultiple functional entities, for example methoxy or ethoxy groups, toenable the functionalized silicone compound to become polymerizes, andpossibly even crosslinked, as a result of the coating processes of theinvention.

[0067] The functionalized silicon compound employed in the coatingprocess of the invention should preferably have a structure which willprovide a stable residue on the substrate powder and which will remainstable throughout subsequent processing steps, for example cosmeticformulation steps, that the coated powder is intended to undergo, andwill also remain stable for the intended shelf life of the product. Thesilicon backbone structure of the functionalized silicon compoundstarting material, and the substituents employed, should be selectedwith this end in view. Thus, it is preferred that the backbone structurecomprise a single silicon atom, a pair of silicon atoms connected by asingle covalent bond or a siloxy chain, —(—Si—O—)_(r) where r may be aninteger of from 2 to 200, or even as high as 1,000. Preferably r is from5 to 100, more preferably from 10 to 50.

[0068] Preferred substituents in the silicon compound, besides thefunctional entity or groups, lack chemical reactivity in the processesof the invention and form stable entities in the powder coating. Someexamples of suitable such nonfunctional substituents include saturatedhydrocarbon groups and saturated fluorohydrocarbon groups, particularly,but not exclusively, alkyl and fluoroalkyl groups. Such substituents canhave any number of carbon atoms supporting stable bonding of thesubstituent or substituents to the silicon backbone, for example, from 1to about 50, preferably from 4 to about 35 and more preferably fromabout 7 to about 25 carbon atoms per substituent, preferably with amaximum of 50 carbon atoms per silicon atom. It will be understood thatincreasing the carbon count of the substituent or substituents mayenhance the lipophilicity of the inventive coated powders. However, thisconsideration will need to be balanced against the instability of largersubstituents which may dissociate. Another balancing consideration isthat for enhanced silicone dispersibility, higher proportions of siliconatoms in the coating may be desirable.

[0069] Many suitable functionalized silicon compounds, and equivalentcompounds, additional to those described or suggested herein will beapparent to those skilled in the art in light of the disclosure hereinor will become apparent as the art develops.

[0070] Some suitable functionalized silane compounds for use in thepresent invention have a structure illustrated by the following Formula3:

(R³O—)_(x)—Si—(—R⁴)_(y)  (3)

[0071] wherein:

[0072] R³ is methyl, ethyl, propyl or butyl;

[0073] R⁴ is a saturated, unsaturated or polyunsaturated, straightchain, branched, unsubstituted cyclic, substituted cyclic alkyl or alkylphenyl group having from 3 to 60 carbon atoms, preferably a saturatedalky group having from 7 to 25 carbon atoms; and x+y=4.

[0074] The structures depicted include mono- and dialkoxy silanes inaddition to trialkoxysilanes, all of which can react with pigmentsurfaces, However, di- and tri-alkoxy silanes are particularlyadvantageous for their abilities to form polymers (or oligomers) andcrosslinked networks which are chemically and physically stable. Inpractice, trialkoxysilanes, such as those specifically mentioned hereinare particularly suitable for employment in the invention being activeand commonly used as functionalized silicon coating materials.

[0075] Some preferred functionalized silicon compounds for use in thepractice of the invention have the following Formula 4:

[0076] wherein R³ and n are the same as above and preferably R³ ismethyl or ethyl and n is from 7 to 25.

[0077] Some examples of suitable functionalized silanes include:organoalkoxysilanes having an organic group or groups which may beunsubstituted or substituted or a mixture of different groups includingfor example, methyltrimethoxyalkylsilane, phenyltrimethoxyalkylsilane,and diphenyldimethoxy alkylsilane, as well as silanes havingaryl-substituted organic groups, for example,gamma-methacryloxypropyl-trimethoxysilane wherein the alkyl grouppreferably has from 7 to 25 carbon atoms, more preferably from 8 to 12carbon atoms and the aryl group is preferably a saturated hydrocarbon,save for benzene ring unsaturation, for example phenyl or alkylphenylwith up to 25 carbon atoms.

[0078] Functionalized silicon compound coating agents, or startingmaterials, employable in the invention can include suitablepolysiloxanes such for example as a polysiloxane compound of thefollowing Formula 5:

[0079] wherein:

[0080] R⁵ is CH³ or or H;

[0081] X is H or OH; and

[0082] q is from 1 to about 1,000, preferably not more than about 100and more preferably from about 5 to about 60.

[0083] The R⁵ substituents can all be hydrogen or all be methyl with thepresence of hydrogen rather than methyl being desirable for highervalues of q to provide additional reactive sites. Alternatively, the R⁵substituents can be a mixture of hydrogen and methyl groups, for examplea 1:1 mixture. The mixture can be any desired proportion of the twosubstituents, for example from 3:1 to 1:3. “Mixture” is here used toindicate that one or more siloxy units has a hydrogen substituent at R⁵,and one or more siloxy units has a methyl substituent at R⁵.

[0084] This structure includes three classes of polysiloxane compoundthat are commonly used to coat pigments especially cosmetic pigments,namely: methyl hydrogen polysiloxane wherein X═H and R═CH³; methylhydrogen polysiloxane and dimethylpolysiloxane copolymer wherein X═H,R═CH₃ or H; and dimethiconol wherein X═OH, R═CH₃. Compounds containingmethyl hydrogen polysiloxane can bond chemically to the powder substrateby reaction of a Si—H group while dimethiconol can bond to the pigment,or other powder, chemically via crosslinking through reaction with a di-or tri-alkoxy titanate. Suitably functionalized dimethicone compoundsmay also be employed, with either backbone or terminal functionalsubstituents. Useful functionalized polysiloxanes can comprise fromabout 1 to about 100 siloxy groups per functional group, desirably fromabout 3 to about 20 siloxy groups per functional group.

[0085] The polysiloxane compounds, groups or units employed in theinvention or generated in the coating may include polymeric chainshaving up to 100 or even up to 1,000 repeating —Si—O— units, wherein atleast one Si atom of each chain is linked to the powder surface throughan oxygen atom. The chains can be cross-linked to each other as well.The remaining functional sites of each Si atom in the chain can beoccupied by a variety of groups as will be apparent from thisdisclosure, including hydrogen, methyl, C₂-C₃₀ alkyl or alkenyl, and/orphenyl, and equivalents thereof, resulting in units such as—Si(CH₃)(C₆H₅)O—, —Si(CH₃)(H)O—, or —Si(H)(C.₆H₅)O—, and generallycapped with —Si(CH₃)₃.

[0086] Some further examples of embodiments of functionalized siliconesuseful in the practice of the invention include alkoxy-substitutedbranched silicones of intermediate size, having for example from about10 to about 100 siloxy groups per molecule, preferably from about 15 toabout 40 siloxy groups per molecule. Optionally, such a branchedsilicone can have a relatively long backbone of for, example from about4 to about 50 siloxy units, preferably from about 8 to about 30 siloxyunits, with a small number of side chains, for example from about 1 toabout 10 side chains, preferably from 2 to 5 side chains. The sidechains can have the same or different numbers of siloxy groups, forexample from about 1 to about 12 siloxy groups, preferably from 3 to 8siloxy groups.

[0087] Such a branched silicone can be functionalized with a smallnumber of alkoxy groups, e.g. methoxy or ethoxy groups, preferablymethoxy groups, for example from about 1 to about 10 alkoxy groups,preferably from 2 to 5 alkoxy groups. Preferably, the alkoxy groups arenot terminal groups, although some could be, and preferably they areattached to the backbone of the branched silicone. However, in otherembodiments one or more alkoxy groups can be attached to one or moreside chains, if desired.

[0088] In still further embodiments of such branched silicones one ormore, or all, of the alkoxy groups can be replaced by another suitablefunctional group as described herein, for example a chloro group.

[0089] The siloxy groups are preferably dimethylsiloxy groups, orpossibly diethylsiloxygroups although other lower alkyl groups, e.g. upto about 10 carbon atoms may be attached to the silicone atoms, ifdesired, as will be apparent to those skilled in the art. A smallnumber, e.g. less than 10, of the siloxy groups may be methyl hydrogensiloxy groups if desired. If methyl hydrogen siloxy groups are employedfewer or no alkoxy or other functional substituent may be required.

[0090] One specific example of a suitable such branched siliconecompound is product KF-9908 supplied by Shin-Etsu Chemical Co., Ltd.(Tokyo, JP) which is believed to have the following formula (6)

[0091] wherein each node or angle represents an oxygen or silicon atomand the siloxy chains are methyl-terminated dimethyl siloxy chains. The—OR groups are methoxy or ethoxy.

[0092] Some alternative embodiments of branched silicone compound usefulin the practice of the invention are similar to those just describedwith the addition of a number of alkyl side chains attached to thesiloxy backbone, of length of from about 1 to about 30 carbon atoms.Optionally the alkyl side chains can be interposed between the siloxyside chains to alternate with the siloxy side chains. An example of sucha compound is product KF-9909 available from Shin-Etsu Chemical Co.

[0093] A still further alternative group of compounds constitutingfunctionalized silicone compounds useful in the practice of theinvention comprise compounds complying with formula (6) as describedabove, wherein the backbone or main chain is a polyacylate chain ratherthan a polysiloxy chain, the side chains being siloxy chains, asdescribed above, rather than alkyl groups. The acyl monomers of thepolyacylate backbone can have from about 1 to about 10 carbon atoms,preferably from 2 to 5 carbon atoms.

[0094] Employment of polyfunctional silicon starting materials havingmore than two functional entities per unit can provide a crosslinkedcoating of exceptional durability.

[0095] Many suitable functionalized silicone compound startingmaterials, comprising one or more functionalized silicone compounds,that are useful in the practice of the invention are known and some aredescribed, by way of example in: Law, et al. U.S. Pat. No. 4,113,665(Ameron), for example at column 2, lines 13 to 47 and column 3, line 17to column 7, line 19; Socci, et al. U.S. Pat. No. 4,832,944 (Revlon),for example, at column 2, lines 21-51; Hollenberg, et al. U.S. Pat. No.5,143,722, for example at column 2, line 43 to column 3, line 62;Hasegawa U.S. Pat. Nos. 5,368,639 and 5,458,681 (Miyoshi Kasei), forexample at column 2, line 24 to column 2, line 48 of the '639 patent;Mitchnick, et al. U.S. Pat. No. 5,486,631 (Siltech and SunSmart), forexample at column 2, line 49 to column 4, line 38; Mitchnick, et al U.S.Pat. No. 5,536,492 (Siltech and SunSmart); Horino, et al. U.S. Pat. No.6,200,580 (Miyoshi Kasei) for example at column 3, lines 33-53 andcolumn 6, line 55 to column 7, line 67; and Colton, et al. United StatesPatent Application 20020061407 (PPG) for example at paragraphs[0020]-[0022]. The specific passages cited, as well as the entiredisclosures, of each of the patent publications identified in thisparagraph are hereby incorporated herein by this specific referencethereto.

[0096] Some other suitable functionalized silicone compound startingmaterials useful in the practice of the invention include fluorinated oralkyl fluorinated analogs of the silicone compounds described in theforegoing patents, which fluorinated or alkyl fluorinated analogs can,without this being a requirement, have the desirable structuralcharacteristics for fluorinated or alkyl fluorinated functionalizedsilicone compound starting materials to be employed in the presentinvention that are described hereinbelow.

[0097] The invention also includes the modification of known siliconecoating processes and products such as those described in the foregoingpatents or other literature, by the inclusion of an organometallate inthe described silicone coatings or processes to provide hybridsilicone-organometallate coated powders. Furthermore, the presentinvention can include in its processes and products the use of reagents,reactants, reaction conditions and treatment methods and steps describedin the foregoing patents or other literature for the purpose of coatingpowders with silicon-containing materials, as will be understood bythose skilled in the art in light of the teachings herein.

[0098] Fluoro- and Fluoroalkyl Silicon Compounds

[0099] If desired, the functionalized silicon compound starting materialmay be fluorinated and thereby provide fluoro substituents in the powdercoating. Fluorinated silicon compounds have excellent hydrophobicity butrelatively poor affinity for lipids, are expensive and may be unstableat an alkaline pH.

[0100] Such fluorination, or perfluorination wherein a carbon atom isfully fluorinated, may comprise one, two, three or more fluorosubstituents each in one or more hydrocarbon groups, being groupsattached directly to a silicon atom in the silicon compound. Ifsaturated, which is preferred in the practice of the invention, suchfluorohydrocarbon groups may be expected to manifest themselves in thecoating agent in a chemically unchanged state. In one embodiment, thefunctionalized silicon compound comprises a single fluoroalkyl grouphaving not more than about 30 carbon atoms and from 1 to about 12fluorine atoms.

[0101] Alternatively, the fluorination of the silicon compound couldcomprise one or two fluorine atoms bonded directly to a silicon atom.However, Si—F groups are less preferred because the resultant residue inthe coating may have undesirable reactivity.

[0102] Some embodiments of the invention can employ as startingmaterials one or more fluorosilane compounds having the structure shownin the following Formula 7:

(R¹O—)_(b)—Si—((CH₂)_(d)—(CF₂)_(e)—F₃—)_(c)  (7)

[0103] wherein:

[0104] R¹ is as defined above, broadly stated, a 1-12 carbonhydrocarbon;

[0105] b is 1, 2 or 3;

[0106] b+c=4;

[0107] d is from 0 to about 3; and

[0108] e is from about 3 to about 20.

[0109] It will be understood that other functional groups than thealkoxy groups can be employed if desired and that the fluoroalkyl groupshown may be used in other compounds where a fluoroalkyl group, has beenreferenced or would be seen to be suitable herein.

[0110] In addition suitable fluorinated functionalized siliconecompounds that can be used in the practice of the invention aredisclosed in: Farer U.S. Pat. No. 6,471,950, for example at column 2,lines 30-63; Goodwin U.S. Pat. No. 5,328,768 (PPG), for example atcolumn 2, lines 6-25; and O'Lenick Jr. et al. U.S. Pat. No. 6,524,705(Phoenix Research) for example at column 2, lines 38-63 and column 4,lines 37-48.

[0111] In addition, fluorinated silicon compounds or fluorosilanes suchas those disclosed in U.S. Pat. No. 5,473,038 O'Lenick, Jr. (Siltech)and Arnaud U.S. Pat. No. 6,203,780 (L'Oreal) can be employed as startingmaterials for the coating processes of the present invention whensuitably functionalized by the inclusion in the molecule, if not alreadypresent, of one or more functional groups, for example hydroxy, methoxyor ethoxy groups, as has been described herein with reference tonon-fluorinated compounds. Two or three such groups are preferred toprovide for the possibility of a polymerized residue in the coating.

[0112] The entire disclosures of each of the foregoing patentpublications relating to fluorinated silicon compounds are herebyincorporated herein by this specific reference thereto.

[0113] It will be understood that the above-described fluorinatedfunctionalized silicon compounds can be employed in the processes of theinvention in place of or as well as the nonfluorinated functionalizedsilicon compounds to yield coatings including fluorinated groups. Ifdesired, the fluorinated functionalized silicon compounds admixed with,or otherwise combined with the nonfluorinated functionalized siliconcompounds, as coating agents, in approximate proportions of from 1:10 to10:1.

[0114] Hydrocarbon Substituents

[0115] It will be understood that possible hydrocarbon groups in theorganometallate or functionalized silicon compound can have a variety ofstructures and may, for example, include, independently of each other,if the molecule contains more than one hydrocarbon group, a linear orbranched alkyl group, a cycloalkyl group, a substituted or anunsubstituted aryl group or combinations of the foregoing. Preferably,such groups are selected to provide residues having little or morepreferably no significant reactivity in the end product coated powder.

[0116] If desired, either or both the organometallate or the siliconcompound can contain one or more functional coupling groups, or atomsintended to provide a bond to the substrate powder or to the other ofthe organometallate or the silicon compound, which functional entity isborne by a hydrocarbon or fluorohydrocarbon substituent, for example analkyl or fluoroalkyl group. Such an alkyl substituent functional groupmay for example be an ethylenically unsaturated group such as anacrylic, methacrylic, vinylic group or the like, a halogen orhalogenated group, a hydroxyl or hydroxylated group, a carboxyl orcarboxylated group, a thiol or mercaptan group, an epoxy group, an estergroup, a urethane group, a urea group, an amine or amino acid group, apolypeptide group or the like. Where the carrier group for thefunctional entity is a fluoroalkyl or other fluorohydrocarbon group, itis preferred that there is at least one carbon atom, more preferably atleast two carbon atoms between the carbon atom bearing the functionalentity and the closest carbon atom bearing a fluorine atom.

[0117] However, in most cases, for the purposes of the invention it isbelieved preferable for the functional entity to be bonded directly toa, or the, metal atom of the organometallate or to a silicon atom of thesilicon compound, or at least to be not unduly remote from same.Accordingly, where a functional entity intended for coupling in thecoating process of the invention is borne by a hydrocarbon substituent,it is preferred that the functional entity be attached to the fifth orfewer carbon atoms from the metal atom, preferably to an adjacent ornext adjacent carbon atom.

[0118] Solvents

[0119] Suitable solvents for the coating agents may be employed tofacilitate the coating process, if desired. Such solvents should becapable of dissolving the respective coating agent to promote evendistribution of the coating agent over the surface of the substratepowders in a mixing step and of being removed in a drying step. Forexample, water or other suitable solvent may be employed for theorganotitanate or other organometallate, as described in Schlossman '604and a suitable aprotic solvent can be employed for the functionalizedsilane or other silicon compound. Also, if desired, the organometallate,and optionally also the silane, can be solubilized in a volatile organicsolvent such as isopropyl alcohol, heptane, isoheptane, isooctane,isononane and petroleum distillates such as those available fromPhillips Chemical under the trade names or trademarks Soltrol 130,Soltrol 150 and Soltrol 170. and then mix it with or spray it on thematerials to be coated.

[0120] Another useful solvent for functionalized silicon compounds is anisopar solvent. Isopar solvents are a range of solvents each comprisinga high-purity, fractionated partially neutralized mixture ofisoparaffinic acids which are available in different grades such asisopar C, which comprises C₇-C₈ solvents, isopar E or isopar G.

[0121] Preferably, a single solvent, for example isopar C, or a mixtureof solvents, is used to dissolve both the organometallate and thefunctionalized silicon compound in a single homogenous liquid medium.However, an emulsion of two or more solvents could be employed, withdifferent coating agents dissolved in each solvent, on a one-to-onebasis.

[0122] Cosmetic Powders

[0123] Some suitable cosmetic or other powders that can be employed inthis invention include: inorganic and organic pigments and fillers;talc; mica; sericite; kaolin; starches; barium sulfate; calciumcarbonate; porous or non-porous silica in various shapes includingspherical, ellipsoidal, irregular, rod and other known shapes;hydroxyapatite; and hollow or solid polymeric powders or microspheres ofpolymethylmethacrylate, polyvinylidene chloride copolymer, polyethylene,cellulose or nylon or other suitable polymer. Other suitable cosmetic orother powders will be known or be or become apparent to those skilled inthe art.

[0124] The powders employed as substrates in the processes of theinvention may have any desired regular or irregular shape includingspherical or ball like particles with irregular porous surfaces,needles, rods, flakes, rhomboids and so on.

[0125] Some suitable inorganic pigments which may benefit from thehybrid coatings of the present invention include: titanium dioxide; zincoxide; iron oxide; alumina oxide; chromium oxide; mango violet;ultramarines, composites of metal oxides or of a metal oxide and aninorganic salt and any other inorganic pigment powder useful in thecosmetic or other relevant arts. If desired, prior to the inventivecoating treatment, powders such as titanium dioxide, zinc oxide andother inorganic pigments or fillers, may be treated with silica,alumina, boron nitride or other known inorganic coatings, singly or incombinations.

[0126] Some suitable organic pigments include aluminum, barium, calciumand zirconium lakes of FD&C and D&C grades of Red No. 6, Red No. 7, Red21, Red No. 27 and Yellow No. 5. Other suitable inorganic or organicpigments will be known or be or become apparent to those skilled in theart.

[0127] Preferably, the reactants and reaction conditions employed in thecoating processes of the invention are selected to provide covalentbonding to metal oxide, hydroxide, carbonate, silicate or other reactivemoieties on the surfaces of the cosmetic powder particles. However,ionic, hydrogen or van der Waals bonding in addition to, or in thealternative, may also provide satisfactory bonding between the coatingand the substrate powder particle.

[0128] Particle Size

[0129] There is no particular limitation as to the particle size of thepowders employed in the invention. However, a mean particle size in therange of from about 0.01 to about 100 micron is preferred and a meanparticle size in the range of from about 0.01 to about 20 micron is morepreferred. Desirably, at least about 90 percent, preferably at leastabout 98 percent, and more preferably at least about 99.5 percent of theparticles lie within the preferred average particle size range. Somepreferred powders for use in the invention are free of oversizeparticles that may impart grittiness and are also free of overly fineparticles whose presence may be undesirable in the processes of theinvention described herein.

[0130] Proportions

[0131] The quantity, or proportion of hybrid coating material employedin the present invention can be varied according to the nature of thesubstrate and can be selected to provide a coated pigment or othercosmetic powder having good water repellency, smooth feel and goodadhesion to the skin. To this end, the quantity of coating agent shouldgenerally be at least 0.1 percent of the coated product. If the amountis over about 30 percent by weight, the coated powder may be too wet andmay tend to agglomerate unacceptably. Thus, in one embodiment thequantity is in a range of from about 0.1 to about 30 percent by weightbased on the weight of the coated powder, preferably from about 1 toabout 10 percent and more preferably from about 2 to about 5 percent ofthe weight of the coated powder.

[0132] The relative proportion, or ratio, of organometallate to silanecan be varied according to the balance of properties desired. Thus, thehydrophilicity may be increased by increasing the proportion oforganometallate relative to the silane and the silicone fluiddispersibility can be increased by increasing the proportion of silanerelative to the organometallate. Thus, the ratio of organotitanate orother organometallate to silane can be in a range of about 0.1:1 to10:1, but is preferably in a range of about 0.4:1 to about 3:1. Aproportion within about ten or twenty percent of equality is useful toprovide a balance of properties.

[0133] Coating Process

[0134] In one embodiment of a process aspect of the invention, theinvention provides a cosmetic powder hydrophobizing process comprising:

[0135] a) combining:

[0136] i) a powder to be coated;

[0137] ii) a liquid dispersion medium sufficient for a slurry;

[0138] iii) an organometallate compound of formula (1); and

[0139] iv) a functionalized silicon compound; to form a slurry;

[0140] b) thoroughly mixing the slurry;

[0141] c) filtering the slurry; and

[0142] d) heating the resultant paste to a temperature and for a timeeffective to yield a dry powder.

[0143] Some examples of suitable elevated temperatures are in the rangeof from about 60 to about 130° C., and of suitable times in the range offrom about two to about ten hours. Other suitable times and temperatureswill be known to those of ordinary skill in the art, having regard tothe materials employed, or can be determined without undueexperimentation. Optionally drying may be conducted under vacuum.

[0144] The slurry may be prepared in a variety of ways, as will beapparent to those of ordinary skill in the art. For example, a blend ofthe organometallate and the functionalized silicon compound coatingagents can be added to the powder to be coated and a suitable liquidmedium to form a slurried mixture. Alternatively, the coating agents maybe dissolved in one or more solvents, which optionally may be emulsifiedand mixed or sprayed on to the powder. Preferably, a single solution ofa blend of the two coating agents, each of which may comprise one ormore compounds, e.g. compounds of formulae I and II, respectively, ismixed with the powder or powders to be coated, preferably by spraying onto the powder while mixing. However the ingredients are broughttogether, it is desirable to thoroughly mix the slurry until homogeneityis achieved, with a view to ensuring that the entire surface of eachpowder particle is wetted.

[0145] Any suitable additives that are customary employed in pigmentcoating processes may be included in the mixture, if desired. Forexample, various acids, including low molecular weight aqueous organicacids, such as acetic acid, can be used to catalyze the hydrolysis offunctionalized silane starting materials. Also, trivalent iron2-ethylhexanoate or zinc 2-ethylhexanoate can be employed to catalyzereaction of methicone with substrate powder materials. However, in manycases use of such additives or catalysts is not necessary.

[0146] If desired, the dried, hybrid-coated powder produced by thisprocess can be pulverized in a mill, for example a jet mill, hammermill, or other suitable mill.

[0147] The resultant alkylpolysiloxane, or alkylpolysiloxane residue, inthe hybrid powder coating preferably has a degree of polymerization offrom about 5 to about 100, more preferably from about 10 to about 15.

[0148] Other processes for producing hybrid coated powders pursuant tothe present invention include a two-stage process wherein the powder isfirst coated with the organometallate and is then coated with thefunctionalized silicone compound. If desired, the organometallate powdermay be dried prior to coating with functionalized silicone compound.Preferably, such intermediate drying step is curtailed or moderated toavoid fully curing the organometallate residues so that theorganometallate coated powder particles retain sufficient surfacereactivity to effectively bond with the functionalized silicone compoundin the second stage of the process. The intermediate drying step isfollowed by a final drying step, to completely cure the hybrid coating,after the functionalized silicone compound has been applied. Such atwo-stage process is contemplated as providing an outer surface of thehybrid coated powder particle which is particularly rich in siliconatoms and accordingly has excellent silicone fluid dispersibility.

[0149] Alternatively, the functionalized silicone compound could beapplied in a first stage prior to application of the organometallate ina second step, with or without the intermediate drying step. However,the good reactivity of preferred organometallates and their ability tobind effectively with both pigment powder surfaces and many siliconematerials renders the application of the organometallate prior to thefunctionalized silicone compound a particularly attractive two-stageprocess. Such process is believed preferably to coating withorganometallate before silicon because the organometallate may be lessresistant to heat. Furthermore, application of the organometallate on toa silicone coated powder substrate is believed advantageous in reactingwith residual reactive groups that may remain in the silicone coating,especially on the outer surface thereof.

[0150] Optionally each stage may employ a suitable solvent for therespective coating agent, which solvent is sufficiently volatile to beremoved by drying.

[0151] Preferably, the herein described coating agents are the onlyreactive coating materials employed. Thus, the reactive coatingmaterials employed in the coating compositions and processes of thepresent invention preferably consist essentially of an organometallateand a functionalized silicon compound each of which may be one or moreof the respective compounds described herein as being useful coatingagents.

[0152] Coating Structure

[0153] Possible chemical structures of the inventive hybrid powdercoating are more fully described hereinbelow. Preferred coatingscomprise a continuous, complete, coherent coating over the entire outersurface of each powder particle which coating is tenaciously covalentlybonded to the powder substrate. Preferably, also the coating has atleast one covalent bond to the powder particle substrate for every 100metal or silicon atoms in the coating agent, more preferably for every20 such atoms, and still more preferably for at least every 10, or even5 such atoms.

[0154] It will be understood that an alkylpolysiloxane coating agent canprovide a residue in the powder coating in the form of a chain of siloxyunits. These siloxy units may be terminated with, or interspersed with,organometallate units, may have varying degrees of crosslinking and willhave at least some terminal units bonded to the powder substrate. Otherterminal units may be capped with organometallate groups or may, in somecases, comprise free hydroxyl groups.

[0155] One embodiment of coating according to the invention can have thefollowing structural formula (8), employing titanium as an exemplarymetal:

[0156] wherein a is from 1 to 1000, preferably from 1 to 100. Theparticular value of a will depend upon the starting materials andreaction conditions employed, as will be apparent to those skilled inthe art. The structure shown can repeat throughout the coating. Theunsatisfied valencies can be occupied by other similar units, some ofwhich may serve as cross links, e.g. through oxygen atoms, powdersubstrate atoms or groups, or any of the various residual groupsdescribed or implicit herein. Valencies not made to other units arepreferably satisfied with hydrocarbon or fluorohydrocarbon groups orfatty acid ester groups, as will be apparent from the disclosure herein.Although only one Si—O—Ti group is shown, in some instances multiples ofthis group may also chain together. However such poly(siloxy-metal)chains are not generally believed to be present to a significant extentin the resultant coatings.

[0157] Reaction of the organotitanate coating agent with a silicone aswell as the coated powder can provide a structure in the finishedcoating comprising —Si—O—Ti— units in addition to the conventionalpolysiloxane backbone units —Si—O—Si—. Thus, such coatings of thepresent invention have a quite different chemical character fromconventional silicone coatings.

[0158] Organometallate starting materials having only a singlefunctional entity can be expected to yield coatings wherein singleorganometallate units are covalently bound to the powder surface and tomultifunctional siloxy units that are also covalently bonded to thepowder surface, if such siloxy units are present.

[0159] If both the organometallate compound and the functionalizedsilicon compound are unifunctional, then the coating can be expected toconsist essentially of a mosaic of single units of each compound whichpreferably extends continuously, without interruption, over the surfaceof each cosmetic powder particle. The relative affinities of the coatedparticles for lipids or silicone fluids will depend upon the relativesurface areas the two different units occupy as well as the particularhydrophobic or silicic character of the respective units. In turn, therelative surface areas occupied can be expected to depend upon themolecular sizes and reactivities of the respective starting materials.The respective dispersibilities of the inventive hybrid coated powdersin lipids and silicones can be adjusted by varying these parameters asmay be determined empirically by the simple experiments describedherein.

[0160] Organometallate starting materials having two or more functionalentities, e.g. two alkoxy groups, can be expected to yield coatingswhich in addition to the features described in the immediately precedingparagraph include siloxy units coupled to the particle surface throughan organometallate unit. Possibly, di-, tri- or polyorganometallateunits may bond to the particle surface. However such structures arebelieved to have only limited stability under most relevant reactionconditions and to fairly readily break down to yield a singleorganometallate unit bonded to the powder surface.

[0161] Of particular interest in the practice of the invention arecoated powders formed from difunctional organometallate compounds anddifunctional silicon compounds. The resultant coatings can includechains of polysiloxy units coupled to the powder, and possibly alsointerconnected one to another, by metallate units and may contain—Si—O—M— units wherein valencies not shown are satisfied withsubstituents present in the starting materials, for example alkyl orester groups. Such structures are believed desirable in providingdurable and cohesive coatings that are tenaciously bonded to thecosmetic powder particles.

[0162] While the invention is neither bound nor limited by anyparticular theory, but only by the appended claims, it is known, forexample from DuPont Tyzor® Organic Titanates, Dupont SpecialtyChemicals, 11/93, 233629A, that organic titanates are useful for thecatalysis and crosslinking of silicones and can catalyze polymerizationof various siloxanes for coatings, providing harder surfaces, improvedheat and electrical resistance, adhesion, water repellency andresistance to heat and staining. However, that cosmetic powders couldobtain improved dispersibility in oils and silicone fluids as a resultof the hybrid coatings of the present invention was neither known orsuggested. Based on the aforementioned knowledge, it is contemplatedthat the incorporation of organometallates in the inventive coatings mayresult in a more complete reaction of compounds such as methyl hydrogenpolysiloxane or methyl hydrogen polysiloxane and dimethylpolysiloxanecopolymer with pigment, e.g. more complete reaction of their Si—Hgroups, lowering the potential for the generation of hydrogen over time,for example during storage, by the coated pigment.

[0163] Furthermore, complete, or essentially complete, reaction offunctionalized silicon compounds such as methyl hydrogen silicone may beeffective in reducing or eliminating problems of color shift, possiblyby reducing long term surface reactivity and resultant particleagglomeration.

[0164] It will be understood that each of the organometallate andfunctionalized silicon starting materials may itself constitute amixture of materials of various functionality, with the resultingcoatings having a blend of the above-described structures.

[0165] It will also be understood that whereas the structures of thenovel powder coatings of this invention, and possibly also of some ofthe starting materials, are described in terms of covalent bonds, suchdescriptions may be idealized and the actual chemical structures may andprobably will display some characteristics of ionic, hydrogen and vander Waals bonding, without departing from the teachings herein.

[0166] The invention also includes a lipid- and silicone-dispersiblecoated cosmetic powder comprising cosmetic powder particles and ahydrophobic coating on the cosmetic powder particles, the hydrophobiccoating conferring lipid and silicone dispersibility on the cosmeticpowder particles and comprising:

[0167] a) cosmetically stable hydrophobic organometallate units offormula (R⁶)_(g)M₁—O— wherein:

[0168] M₁ is a metal capable of forming cosmetically stableorganometallate compounds of the structure shown, including any of themetals M;

[0169] a equals the valence state of metal M₁ minus 1 or minus 2,wherein, in the case of the latter alternative, the available valence ofmetal M₁ is covalently bonded to another M₁ atom or to a coatingmaterial oxygen atom;

[0170] R⁶ is a hydrophobic organic moiety including a cosmeticallystable covalent bond to metal M or, when a is greater than 1, to anoxygen atom with an available valence and wherein multiple R⁶s, ifpresent, may be the same or different; and

[0171] b) cosmetically stable siloxy units of formula D_R⁷_R⁸_Si—O—,“Formula (9)” hereinafter, wherein:

[0172] D is an oxygen atom with an available valence or a hydrophobicorganic moiety including a cosmetically stable covalent bond to thesilicon atom; and

[0173] R⁷ and R⁸ may be the same or different and are each a hydrophobicorganic moiety including a cosmetically stable covalent bond to thesilicon atom;

[0174] wherein the hydrophobic coating is covalently bonded to thecosmetic powder by satisfaction of available oxygen valencies in theorganometallate and siloxy units.

[0175] Some preferred embodiments of R⁷ and R⁸ include optionallysaturated hydrocarbon or fluorohydrocarbon groups having from 1 to 30carbon atoms and other such groups as will be apparent from thedisclosure herein. Other possible groups for D include the same groupsas for R⁷.

[0176] The organometallate units in Formula (9) include units having twoavailable oxygen valencies, at least one of the two organometallate unitavailable oxygen valencies being satisfied by a covalent bond to one ofthe siloxy units or to another organometallate unit, and the hydrophobiccoating can include siloxy units bonded to the powder throughorganometallate units.

[0177] The siloxy units in Formula (9) include units having twoavailable oxygen valencies at least one of the two siloxy unit availableoxygen valencies being satisfied by a covalent bond to one of the siloxyunits or to another organometallate unit and the hydrophobic coating caninclude polysiloxy units.

[0178] Both the organometallate units and the siloxy units in Formula 7can include units having two available oxygen valencies and thehydrophobic coating includes poly siloxy units bonded to the powderthrough organometallate units.

[0179] The coating can comprise a stoichiometric proportion oforganometallate units to siloxy units of from about 0.05:1 to about10:1, preferably about 0.4:1 to about 3:1.

[0180] Some embodiments of the invention, and of making and using theinvention, are described, without limitation, in the following exampleswhich in conjunction with the foregoing description include the bestmode contemplated of carrying out the invention.

Comparative Example A Isopropyl Titanium Triisostearate-coated TiO₂

[0181] 98 g of titanium dioxide powder, product code X200 from KemiraCorporation, are added to a blender. 5.9 g of a 34% wt/wt solution ofisopropyl titanium triisostearate (referenced “ITT” hereinafter) inisopar C are sprayed on the titanium dioxide powder in the blender underagitation. The slurry mixture is thoroughly blended, transferred to atray and dried at 110° C. for 4 hours. It is then cooled down to roomtemperature and pulverized.

Comparative Example B Triethoxy Octylsilane-coated TiO₂

[0182] Comparative Example A is repeated employing the same quantity oftriethoxy octylsilane in place of isopropyl titanium triisostearate. Thecoated powders obtained from Comparative Examples A and B are used forcomparison in tests such as those described hereinbelow.

Comparative Examples C-D Coated Red Iron Oxide

[0183] Comparative Examples A and B are repeated employing the samequantity of red iron oxide from Sun Chemical Corporation in place of thetitanium dioxide powder to yield ITT-coated red iron oxide (ComparativeExample C) and triethoxy octylsilane-coated red iron oxide (ComparativeExample D). The resultant coated powders are used for comparison intests such as those described hereinbelow.

Example 1 Hybrid Coating of TiO₂

[0184] 98 g of titanium dioxide powder, product code X200 from KemiraCorporation, are added to a blender. 5.9 g of a 34% wt/wt solution of ahybrid coating mixture (about 2% by weight of the coated product)comprising equal parts of isopropyl titanium triisostearate andtriethoxy octylsilane, referenced “the hybrid coating mixture”hereinafter, are sprayed on the titanium dioxide powder under agitation.The mixture is thoroughly blended, transferred to a tray and dried at110° C. for 4 hours. It is then cooled down to room temperature andpulverized to provide hybrid titanate-silicone-coated titanium dioxidepowder of a desired particle size.

Example 2 Hybrid Coating of Red Iron Oxide

[0185] Example 1 is repeated using 98 g of red iron oxide powder fromSun Chemical Corporation in place of the titanium dioxide powder toyield titanate-silicone-coated red iron oxide powder.

Example 3 Hybrid Coating of Yellow Iron Oxide and Black Iron Oxide

[0186] Example 1 is repeated using 98 g of yellow iron oxide powder orblack iron oxide powder in place of the titanium dioxide powder to yieldtitanate-silicone-coated yellow or black iron oxide powder.

Example 4 Hybrid Coating of Barium Lake

[0187] Example 1 is repeated using 95 g of K 7096 D&C Red 6 barium lakefrom LCW in place of the titanium dioxide powder to yieldtitanate-silicone-coated barium lake powder.

Example 5 Hybrid Coating of Mica

[0188] Example 1 is repeated using a similar quantity of mica in placeof the titanium dioxide powder to yield titanate-silicone-coated micapowder.

Example 6 Hybrid Coating of Silica

[0189] Example 1 is repeated using a similar quantity of silica in placeof the titanium dioxide powder to yield titanate-silicone-coated silicapowder.

[0190] Each of the powders coated with hybrid material produced by themethods of Examples 1-6 shows good water repellency, has a smooth feeland good adhesion to the skin. After mixing and shaking with water, eachhybrid-coated powder floats well and the water soon becomes a similar.

[0191] The properties of the hybrid coated powder products obtainable bythe methods of Examples 1-5 can be determined by various tests, as knownto those skilled in the art, some of which are described below:

Test 1: Hydrophobicity

[0192] In a quick and simple test to determine hydrophobicity, 1 g ofpigment powder is shaken vigorously 10 times in a glass container in 50ml of water. The sample is allowed to stand for one minute and theclarity of the water is observed. Results obtainable are shown in Table1 below. TABLE 1 Hydrophobicity Example A Example B Example 1 Waterphase Cloudy Clear Clear

[0193] The treatment of titanium dioxide pursuant to Comparative ExampleA, employing isopropyl titanium triisostearate, provides a product whichis significantly less hydrophobic than is obtainable with ComparativeExample B, employing a silane, triethoxy octylsilane. Example 1, whereintitanium dioxide is coated with a hybrid composition according to thepresent invention, exhibits comparable hydrophobicity to the silanetreatment of Comparative Example B being also significantly better thanisopropyl titanium triisostearate, Comparative Example A.

Test 2: pH Stability

[0194] 0.5 g of fine coated pigment powder are carefully deposited ontothe surface of 50 g of distilled water having the indicated pH in a 100ml beaker. The time when the pigment powder starts to break the surfaceand sink into the water is observed. Results obtainable are shown inTable 2 below. TABLE 2 pH Stability Time when particles begin to sink pHExample A Example B Example 1 pH4 3 hr. 20 min. >2 weeks >2 weeks pH5 >3days pH6 >3 days pH7 >5 days pH8 >7 days pH9 >7 days

[0195] The pigment treated pursuant to Comparative Example A, isopropyltitanium triisostearate coated, shows loss of hydrophobicity at alltested alkaline, neutral and acid pHs after 7 days, i.e. before 8 days.In the case of acid pHs the loss becomes apparent after about 3 days. Incontrast, both the silane-coated product of Comparative Example B andthe hybrid-coated product of Example 1 of the invention are stable formore than two weeks at all pHs in the test. Both products have ahydrophobicity which is significantly more resistant to acid pHs than isthat of pigment coated with isopropyl titanium triisostearate. Thus, thehybrid coating of Example 1 displays excellent stability over a wide pHrange.

Test 3: Dispersibility in Hydrophobic Fluids

[0196] Various proportions of pigment powder, as shown in Table 3 below,are blended into two different hydrophobic fluids, namely mineral oiland a cyclomethicone product, for example GE Silicones product numberSF1528 which is described as a water-in-oil silicone emulsifiercomprising a 10% silicone polyether copolymer dispersed incyclopentasiloxane (a cyclomethicone). The viscosities of the resultantdispersions are determined by known methods and results obtainable areshown in Table 3 below from which it may be seen that, surprisingly thehybrid coated pigments of the invention have good dispersibility in bothoils and silicone fluids. TABLE 3 Dispersibility in Hydrophobic FluidsIn Mineral Oil In Cyclomethicone Pigment Tested Solids % ViscositySolids % Viscosity Titanium dioxide Uncoated 40 346,000 73 N/AComparative Example A: 80 108,400 75 1,316,000 ITT*-coated ComparativeExample B: 80 698,000 75 505,000 Silane-coated Invention Example 1: 80286,000 75 761,000 Hybrid-coated Red Iron Oxide (Cosmetic russet)Uncoated 50 N/A 60 1,312,000 Comparative Example C: 75 121,200 73824,000 ITT*-coated Comparative Example D: 75 627,000 73 292,000Silane-coated Invention Example 2: 75 126,400 73 488,000 Hybrid-coated

[0197] The uncoated pigments are difficult to disperse in either liquid.Even at the lower solids loadings indicated the resultant dispersion iseither very viscous or the viscosity cannot readily be measured. Theinventive hybrid coating, Examples 1 and 2, improves the dispersibilityof both titanium dioxide and red iron oxide significantly over theuncoated pigment powders.

[0198] Furthermore, the hybrid coated pigment powders of the inventionexhibit significant lipophilicity as shown by a marked improvement inthe dispersibility, of both pigment powders in oils, e.g. mineral oil,as is indicated by the relatively lower viscosities in such a medium,that are shown in Table 3. In the case of red iron oxide, the hybridcoating of Example 2 is almost as effective as the isopropyl titaniumtriisostearate coating of Comparative Example C.

[0199] In contrast, the silane-coated pigments of Comparative Examples Band D which disperse well in the cyclomethicone fluid, yield highlyviscous dispersions in mineral oil, indicating poor lipophilicity.

[0200] Results for the dispersibility of the pigments in cyclomethiconeshow that the hybrid-coated pigment of Examples 1 and 2 is has gooddispersibility in silicone fluids such as the above-describedcyclomethicone material, showing a substantial reduction in viscosity ascompared with the isopropyl titanium triisostearate treated pigments ofComparative Examples A and C or the uncoated pigments. or compatibleprovides a as effectively as silane coating.

[0201] Test C shows that the inventive hybrid coating can provide acombination of desirable properties which are exhibited individually byisopropyl titanium triisostearate and silane coatings, namely both goodlipophilicity and good silicone fluid dispersibility.

Test 4: Stability during Grinding

[0202] To determine the stability of the pigment coating duringgrinding, the coated pigments are dispersed in a suitable cosmeticpigment emulsifier using a mixer and are ground in a mill. Employing anemulsifier supplied by Goldschmidt Chemical Corp., Hopewell, VA underthe trademark ABIL® WE 09, the results described in Table 4, below areobtainable. The ABIL® WE 09 emulsifier is described as comprising amixture of (polyglyceryl-4 isostearate, cetyl dimethicone copolyol andhexyl laurate. TABLE 4 Grinding Stability Dispersion Formula Odor 70parts ITT-coated TiO₂ 30 parts emulsifier Slight waxy odor (ComparativeExample A) 70 parts hybrid-coated TiO₂ 30 parts emulsifier Little, ifany odor. (Invention Example 1)

[0203] The hybrid coating of Example 1 has a dispersibility in theemulsifier, for example Abil® WE 09 emulsifier, which is comparable withthat of the isopropyl titanium triisostearate coating, yet generateslittle or no odor, an important consideration for the aesthetics offinished consumer products.

Comparative Example E Methicone-coated TiO₂

[0204] 96 g of ultrafine titanium dioxide powder, product code A0189from ISK Co., Japan, average particle size no greater than 100 nm, areadded to a blender. 11.76 g of a solution of methicone (34% wt/wt)product code KF-9901 from Shin-Etsu Chemical Co. Ltd. in isopar C aresprayed on the powder under agitation. The mixture is well blended,transferred to a tray and dried at 110° C. for 4 hours. It is thencooled down to room temperature and pulverized to a desired particlesize. The methicone-coated titanium dioxide powder obtained shows poorhydrophobicity. After mixing and shaking with water, the powderdisperses into water and the water remains cloudy indicating poorhydrophobicity.

Comparative Example F Methicone-coated ZnO

[0205] Comparative Example E is repeated with the difference that asimilar quantity of ultrafine zinc oxide powder, average particle sizeno greater than 100 nm is employed in place of the titanium dioxidepowder. A similar result is obtained.

Example 7 Hybrid Coating of TiO₂ Employing Methicone

[0206] Comparative Example E is repeated except that 11.76 g of asolution of a mixture of ITT (17% wt/wt based on the solution) andmethicone (17% wt/wt based on the solution) in isopar C is employed inplace of the solution of methicone. The hybrid titanate-methicone-coatedtitanium dioxide powder obtained shows excellent hydrophobicity. Aftermixing and shaking with water, the powder floats well and the water soonbecomes clear, indicating excellent hydrophobicity.

[0207] Comparing Example 7 with Comparative Example E shows that coatingof ultrafine titanium dioxide with the inventive hybridtitanate-methicone composition yields a product with surprisinglysuperior hydrophobicity to that of a conventionally treated methiconecoated product. In addition, while the invention is not limited by anyparticular theory, it is hypothesized that use of an organotitanate, orother organometallate pursuant to the invention may result in morecomplete reaction of the methicone —Si—H groups, relieving the problemof spontaneous hydrogen generation in storage to whichmethicone-containing products are subject. In addition,methicone-induced color shift during storage is expected to beinhibited.

Example 8 Hybrid Coating of ZnO Employing Methicone

[0208] Example 7 is repeated with the difference that a similar quantityof ultrafine zinc oxide powder, average particle size no greater than100 nm, is employed in place of the titanium dioxide powder. A similarresult is obtained.

Example 9 Oil-in-Water Liquid Makeup

[0209] The following ingredients are employed in the proportionsindicated to prepare an oil-in-water liquid makeup: % Part A LanolinAlcohol (and) Mineral Oil 11.50 Cetyl esters 3.20 Stearic Acid 3.50Glyceryl Monostearate 1.80 Talc 2.00 Titanium dioxide (w/hybrid coating)4.00 Yellow iron oxide (w/hybrid coating) 1.00 Red iron oxide (w/hybridcoating) 0.40 Black iron oxide (w/hybrid coating) 0.15 Part B Propyleneglycol 12.00 Triethanolamine 1.00 PE 20 Sorbitan Monolaurate 0.65Magnesium Aluminum Silicate 1.00 Carboxymethyl Cellulose 0.30 DeionizedWater 57.20 Preservatives and Fragrance QS

[0210] The titanium dioxide and iron oxide pigments are provided withhybrid coatings pursuant to the invention, for example as described inExamples 1-3. The ingredients of Part A are combined, in the ordershown, while thoroughly mixing each component until homogenous beforeadding the next ingredient. The mixture is heated to 60° C. Theingredients of Part B are combined in a separate vessel. The mixture ofPart B ingredients is slowly added to the Part A mixture with goodmixing and the product is poured into suitable containers. A highquality product is obtained.

Example 10 Liquid Compact Foundation (Hot pour)

[0211] The following ingredients are employed in the proportionsindicated to prepare a hot pour liquid compact foundation: % Part ATitanium dioxide (w/hybrid coating) 26.76 Red iron oxide (w/hybridcoating) 0.54 Yellow iron oxide (w/hybrid coating) 0.54 Black iron oxide(w/hybrid coating) 0.16 Mica (w/hybrid coating) 10.00 Silica (spherical)(w/hybrid coating) 2.00 Part B Squalene 10.00 Dimethicone (5 cst) 17.00Octyl hydroxystearate 7.00 Polyglyceryl-3 diisostearate 3.00Microcrystalline wax 7.00 Octyl palmitate 7.00 Carnauba wax 1.00 Part CNylon-12 8.00

[0212] Each of the pigment materials in Part A is provided with a hybridcoating pursuant to the invention, for example as described in Examples1-5. The ingredients of Part A are micronized until the color is fullydeveloped. The ingredients of Part B are heated, with stirring, to about90-93° C. (195-200° F.). Continue to stir for {fraction (1/2)} hour. AddPart A to Part B and mix until homogeneous. Cool to about 82° C. (180°F.). The Part C ingredient and mixing is continued until the mixture ishomogeneous and is then poured into pans at about 74-77° C. (165-170)°F. A high quality product is obtained.

Example 11 Lipstick

[0213] The following ingredients are employed in the proportionsindicated to prepare a hot pour liquid compact foundation: Ingredient %Candelilla Wax 6.00 Carnauba Wax 3.00 Ozokerite 4.00 Paraffin Wax 2.00Yellow Beeswax 6.00 Lanolin Alcohol 6.00 Oleyl Alcohol, 10.00 BHA 0.20Castor Oil 43.25 D&C Red No. 6 Barium 2.50 Lake (w/hybrid coating) D&CRed No. 7 Calcium 2.50 Lake (w/hybrid coating) Iron Oxides (w/hybridcoating) 1.00 FD&C Blue No. 1 0.80 Perfume 0.75 Titanium Dioxide (and)10.00 Mica (w/hybrid coating)

[0214] Each of the pigment materials is provided with a hybrid coatingpursuant to the invention, for example as described in Examples 1-8.Castor oil is placed in the main mixer and heated to 80° C. using asteam pan. The coated lakes, coated iron oxides and the dyes are slowlymixed into the castor oil using a Lightnin' mixer under high speed for30-60 minutes. The candelilla wax, carnauba wax, beeswax, ozokeriteparaffin wax oleyl alcohol and lanolin alcohol are all preheated andmelted together at 80-85° C. using a steam pan and added to the castoroil, pigment and dye mixture. Mixing is continued throughout theaddition of these ingredients.

[0215] The perfume is then added and mixing is continued until themixture is homogeneous. The hybrid coated titanium dioxide and mica,pigments providing pearlescence, are then added and mixing continuesuntil the product is uniform. The lipstick is then cooled and shaped inconventional manner. A high quality product with excellent coverage isobtained.

[0216] The powder coating agents, methods and products of the inventionenable a wide range of cosmetics powders to be coated with the sametreatment and provide a broad spectrum of dispersibility propertiesenabling the coated powders to be utilized in a diversity of mediaincluding aqueous, lipid or oily media and silicone fluids. A particularbenefit of the invention is that a diversity of different powderingredients in a multiphase cosmetic formulation may receive the samehydrophobizing treatment and may in some cases be mixed together andcoated in a single process.

[0217] In summary, the hybrid coating of the invention can provide, inpreferred embodiments, in a single coating, many of the benefits thatare known to be obtainable separately with either an ITT coating or asilane coating. The inventive hybrid coatings can improve thedispersibility of pigments and other powders in oils nearly aseffectively as does an ITT coating and in cyclomethicone nearly aseffectively as does a silane coating.

INDUSTRIAL APPLICABILITY

[0218] The present invention is particularly suitable for application inthe cosmetics industry providing novel and improved coated powderingredients, processes and consumer products such as makeups,foundations, lipsticks and the like. In addition, the novel hybridcoated powders of the invention, coating compositions and processes andend product formulations containing the coated powders may be useful inother industries, for example, in the paints and coatings industries andthe plastics, rubber, adhesives, tile and other industries where thenovel properties of the inventive materials and processes may beadvantageous.

[0219] Other possible fields of application will be known or apparent tothose skilled in the art from the disclosures herein. It will also beunderstood that the particular materials selected for such applicationsin other industries may not be required to meet accepted criteria forcosmetic compatibility, enabling the skilled worker to choose from amonga broad range of possible ingredients the particular ingredients to useto practice the invention.

[0220] Disclosures Incorporated

[0221] The entire disclosure of each and every United States patent andpatent application, each foreign and international patent publication,of each other publication and of each unpublished patent applicationthat is referenced in this specification or elsewhere in this patentapplication, is hereby incorporated herein, in its entirety, by therespective specific reference that has been made thereto.

[0222] While illustrative embodiments of the invention have beendescribed above, it is, of course, understood that many and variousmodifications will be apparent to those of ordinary skill in therelevant art, or may become apparent as the art develops. Suchmodifications are contemplated as being within the spirit and scope ofthe invention or inventions disclosed in this specification.

1. A coated powder having a coating on a powder substrate, the coatingcomprising siloxy metal units.
 2. A coated powder according to claim 1comprising chains of multiple siloxy metal units interconnected byoxygen atoms.
 3. A coated powder according to claim 2 wherein the siloxymetal units have the formula —Si—O—M— wherein M represents a metalhaving two or more valencies and the additional silicon valencies andmetal valencies, if any, are satisfied by chemically inactive groups oratoms compatible with the coated powder and, optionally the siloxy metalunit includes a first oxygen atom boned to the silicon atom and a secondoxygen atom bonded to the metal atom.
 4. A coated powder according toclaim 4 having hydrophobic and lipophilic properties or havinghydrophobic and lipophobic properties.
 5. A coated powder according toclaim 4 having hydrophobic and lipophilic properties and beingdispersible in silicone fluids.
 6. A coated powder according to claim 4wherein the coating comprises a continuous, complete, coherent coatingextending over substantially the entire outer surface of each powderparticle, the coating being tenaciously covalently bonded to the powdersubstrate.
 7. A coated powder according to claim 6 wherein the coatingincludes chains of polysiloxy units coupled to the substrate powder, andmetallate units interconnecting polysiloxy units.
 8. A coated powderaccording to claim 1 wherein the coating includes the residues of amultifunctional organometallate compound, and of a multifunctionalsilicon compound.
 9. A coated powder according to claim 8 wherein themultifunctional organometallate comprises a difunctional organotitanatecompound and the multifunctional silicon compound comprises atrialkoxysilane.
 10. A coated powder according to claim 4 being acosmetic pigment or filler having an average particle size of not morethan about 100 micron.
 11. A coated powder according to claim 4 whereinthe metal M is titanium, aluminum, tin, vanadium, zinc or zirconium. 12.A coated powder according to claim 4 wherein the metal M is titanium,and the coating comprises the residue of a chain of siloxy units, thesiloxy units being terminated with, or interspersed with,organometallate residues wherein the coating includes crosslinking,terminal units bonded to the powder substrate and terminal units cappedwith organometallate residues.
 13. A coated powder having a coating on apowder substrate, the coating having chains of units of the followingstructural formula (8):

wherein a is from 1 to 1000, preferably from 1 to 100 and theunsatisfied valencies are occupied by other units of formula (8), saidother units optionally being crosslinking units, by powder substrateatoms or groups, or by residual unreactive groups.
 14. A coated powderaccording to claim 13 wherein unsatisfied valencies not satisfied byother units are satisfied by hydrocarbon groups, fluorohydrocarbongroups, fatty acid ester groups or mixtures of the foregoing groups. 15.A lipid- and silicone-dispersible coated cosmetic powder comprisingcosmetic powder particles and a hydrophobic coating on the cosmeticpowder particles, the hydrophobic coating conferring lipid and siliconedispersibility on the cosmetic powder particles and comprising: a)cosmetically stable hydrophobic organometallate units of formula(R⁶)_(g)M₁—O— wherein: M₁ is a metal capable of forming cosmeticallystable organometallate compounds of the structure shown, including anyof the metals M; a equals the valence state of metal M₁ minus 1 or minus2, wherein, in the case of the latter alternative, the available valenceof metal M₁ is covalently bonded to another M₁ atom or to a coatingmaterial oxygen atom; R⁶ is a hydrophobic organic moiety including acosmetically stable covalent bond to metal M or, when a is greater than1, to an oxygen atom with an available valence and wherein multiple R⁶s,if present, may be the same or different; and b) cosmetically stablesiloxy units of formula D-R⁷—R⁸—Si—O—, wherein: D is an oxygen atom withan available valence or a hydrophobic organic moiety including acosmetically stable covalent bond to the silicon atom; and R⁷ and R⁸ maybe the same or different and are each a hydrophobic organic moietyincluding a cosmetically stable covalent bond to the silicon atom;wherein the hydrophobic coating is covalently bonded to the cosmeticpowder by satisfaction of available oxygen valencies in theorganometallate and siloxy units.
 16. A coated powder according to claim15 wherein R⁷ and R⁸ include optionally saturated hydrocarbon orfluorohydrocarbon groups having from 1 to 30 carbon atoms and other suchgroups as will be apparent from the disclosure herein.
 17. A coatedpowder according to claim 15 wherein the organometallate units includeunits having two available oxygen valencies, at least one of the twoorganometallate unit available oxygen valencies being satisfied by acovalent bond to one of the siloxy units or to another organometallateunit, and wherein the hydrophobic coating includes siloxy units bondedto the powder through organometallate units.
 18. A coated powderaccording to claim 15 wherein the siloxy units include units having twoavailable oxygen valencies at least one of the two siloxy unit availableoxygen valencies being satisfied by a covalent bond to one of the siloxyunits or to another organometallate unit and wherein the hydrophobiccoating includes polysiloxy units.
 19. A coated powder according toclaim 15 wherein both the organometallate units and the siloxy unitsinclude units having two available oxygen valencies and wherein thehydrophobic coating includes polysiloxy units bonded to the powderthrough organometallate units.
 20. A coated powder according to claim 15comprising a stoichiometric proportion of organometallate units tosiloxy units of from about 0.05:1 to about 10:1.
 21. A process ofproviding a hybrid coating on a cosmetic powder comprising coating thepowder with one coating agent comprising a functionalized siliconcompound and with another coating agent comprising an organometallatecompound under conditions producing a coated powder.
 22. A processaccording to claim 21 wherein the powder is simultaneously mixed withthe functionalized silicon compound and the organometallate.
 23. Aprocess according to claim 21 wherein the functionalized siliconcompound and the organometallate are applied to the powder sequentially.24. A process according to claim 21 comprising: a) combining: i) apowder to be coated; ii) a liquid dispersion medium sufficient for aslurry; iii) an organometallate compound of formula (1) herein; and iv)a functionalized silicon compound; to form a slurry; b) thoroughlymixing the slurry; c) filtering the slurry; and d) heating the resultantpaste to a temperature and for a time effective to yield a dry powder.25. A process according to claim 24 wherein the functionalized siliconcompound comprises a multifunctional silane, a multifunctionalpolysiloxane, a multifunctional fluorinated or fluoroalkyl-silane orpolysiloxane, or a mixture of the foregoing functionalized siliconcompounds.
 26. A process according to claim 21 wherein each coatingagents becomes chemically covalently bonded, under the conditions of thecoating process, to the surfaces of the powder particles and contributesto the provision of a durable outer layer or skin of a hybrid chemicalnature enveloping each powder particle.
 27. A process according to claim26 wherein the coating comprises metal atoms, silicon atoms andoptionally, M—O—Si groups, as defined herein.
 28. A process according toclaim 27 wherein at least one of the coating agents comprises abifunctional coupling agent capable of covalently bonding with thesubstrate powder and with the other coating agent and wherein,optionally, the bifunctional coupling agent has two or more functionalentities.
 29. A process according to claim 21 wherein the coating agentscomprise a mixture of organotitanate and trialkoxy alkylsilane coatingagents and the coated powder is hydrophobic and lipophilic orhydrophobic and lipophobic.
 30. A process according to claim 21 whereinthe organometallate compound provides a hydrophobic residual unit in thepowder coating and optionally comprises a metallate compound having atleast one enduring, unreactive, hydrophobic organic group.
 31. A processaccording to claim 30, wherein the enduring organic group comprises asaturated hydrocarbon optionally containing one or more phenyl groups,the saturated hydrocarbon being attached to a metal atom by an oxygenatom and wherein the organometallate comprises at least one displaceablegroups or atom attached to the metal atom by an oxygen atom to provide afunctional group.
 32. A process according to claim 21 wherein theorganometallate compound is a compound of formula (2) as defined herein.33. A process according to claim 21 wherein the functionalized siliconecompound comprises at least one functional entity capable of covalentlybonding to a target pigment surface, either directly or through anorganometallate residue, under the reaction conditions employed.
 34. Aprocess according to claim 33 wherein the functional entity comprises: alower alkoxy group covalently bonded directly to a silicon atom andhaving from one to four carbon atoms; a halo atom; chloro and aminogroup; an imino group, and/or a hydroxyl group; and ethylenicallyunsaturated group; an acrylic group; a methacrylic group; a vinylicgroup; a halogenated group; a hydroxylated group; a carboxyl orcarboxylated group; a thiol or a mercaptan group; an epoxy group; anester group; a urethane group; a urea group; an amino acid group; or apolypeptide group.
 35. A process according to claim 21 wherein thefunctionalized silicon compound has a structure providing a stableresidue on the substrate powder and remaining stable throughoutsubsequent processing, optionally cosmetic formulation.
 36. A processaccording to claim 35 wherein the functionalized silicon compound has asilicon backbone structure comprising a single silicon atom, a pair ofsilicon atoms connected by a single covalent bond or a siloxy chain offormula —(—Si—O—)_(r) wherein r is an integer of from 2 to 1,000 andwherein, optionally r is from 5 to
 100. 37. A process according to claim35 wherein the substituents in functionalized silicon compound, otherthan the functional entity or groups, lack chemical reactivity in thecoating process and form stable entities in the powder coating, thenonfunctional substituents optionally being selected from the groupconsisting of saturated hydrocarbon groups, saturated fluorohydrocarbongroups, alkyl groups, fluoroalkyl groups, each of the foregoing groupshaving from 1 to about 50 optionally from about 7 to about 25 carbonatoms per substituent.
 38. A process according to claim 21 wherein thefunctionalized silicon compound comprises a functionalized siliconcompound according to formula (3), to formula (4), to formula (5) or toformula (6), each formula being as defined herein.
 39. A processaccording to claim 21 wherein the functionalized silicon compoundcomprises a functionalized fluorinated compound or fluorosilane compoundaccording to formula (7) as defined herein.
 40. A process according toclaim 21 comprising conducting the process under conditions causingreaction of both the functionalized silicon compound and theorganometallate and causing reaction of one or both of thefunctionalized silicon compound and the organometallate with thecosmetic powder.
 41. A particulate pigment treated with a reactivetitanium species and a reactive silicon species under conditions causingreaction of both the titanium and the silicon species and covalentbonding of the residue or residues of both the titanium species and thesilicon species to the pigment surface, providing a coated pigmenthaving hydrophobic properties and lipophilic or hydrophobic andlipophobic properties.
 42. A cosmetic powder coated by a processaccording to claim
 21. 43. A cosmetic product comprising a dispersion ofone or more coated powders according to claim
 42. 44. A cosmetic productcomprising a coated powder according to claim
 1. 45. A cosmetic productaccording to claim 44 comprising a liquid or powder makeup, a lipstick,a nail enamel, an eye shadow or a mascara.
 46. A cosmetic productcomprising a coated powder according to claim
 15. 47. A cosmetic productcomprising a dispersion of an aqueous phase in an oil or in a siliconephase or a dispersion of an oil or silicone phase in an aqueous phasewherein each phase of the dispersion comprises cosmetic powder particlescoated to enhance dispersibility in the disperse medium, a commoncoating material being used to coat the cosmetic powder particles inboth phases of the dispersion.